Related Experiment Video
Updated: Aug 12, 2025
11:48
Microfluidic Chips for In Situ Crystal X-ray Diffraction and In Situ Dynamic Light Scattering for Serial Crystallography
Published on: April 24, 2018
14.8K
Material characterization of GPX®: A versatile in situ solidifying embolic platform technology
Russell J Stewart1, Monika Sima1, Jessica Karz2
1Department of Biomedical Engineering, University of Utah, Salt Lake City, UT, United States.
Frontiers in Bioengineering and Biotechnology
|February 2, 2023
Summary
GPX is a novel liquid embolic agent that solidifies in situ. This versatile platform can be formulated for chemoembolization, offering tunable viscosity and controlled drug delivery for effective vascular occlusion.
Area of Science:
- Biomaterials Science
- Interventional Radiology
- Polymer Chemistry
Background:
- Endovascular embolization is a minimally invasive procedure for occluding blood flow to specific tissues, with expanding clinical applications.
- Liquid embolic agents transition from liquid to solid/semi-solid states within blood vessels, with their solidification mechanism being a key differentiator.
- GPX is a new waterborne liquid embolic agent utilizing electrostatic condensation of polyguanidinium and inorganic polyphosphate for in situ solidification.
Purpose of the Study:
- To characterize the material properties of the GPX liquid embolic agent.
- To evaluate the in vivo effectiveness of GPX in acute animal models.
- To assess the potential of GPX for chemoembolization applications.
Main Methods:
- In vitro characterization of GPX material properties, including viscosity and flow behavior.
- Formulation of GPX with tantalum microparticles or iodinated radiocontrast agents.
- Formulation of GPX with doxorubicin to assess drug loading and release kinetics.
- In vivo evaluation of GPX in swine models for vascular occlusion and contrast properties.
Main Results:
- GPX viscosity is adjustable via polyguanidinium molecular weight and concentration, remaining in a clinically practical range (80-160 cP) and independent of shear rate when formulated with contrast agents.
- Formulation with doxorubicin increased viscosity at low shear rates, exhibiting power-law dependence.
- Effective vascular occlusion and high contrast were achieved in swine kidneys and rete mirabile.
- Iodinated contrast was temporary, while doxorubicin exhibited linear release over 90 days.
Conclusions:
- GPX is a versatile liquid embolic platform with tunable viscosity for injectable, clinically practical flow rates.
- GPX can be formulated with transient or permanent contrast agents.
- The platform supports prolonged, zero-order delivery of doxorubicin to embolized tissues, demonstrating its potential for chemoembolization.
